W & G made slide rules in Australia from about the start of WWII through to the 1960's and possibly early 1970's.

This model rule was made for use as an aid for Surveying and Artillery.

This particular rule appears to have been originally issued by the Australian Army in 1952 but like most modern
forces that body has long gone over to using more modern calculators and computers for these tasks.

I have included a scan of part of the edge of this rule, it shows the lovely grain on the wood used by W & G for these
rules and I have been told that they used either Australian Silver ash or Quondong wood.